I wonder how many BTUh are absorbed by dark colored roof shingles,
as compared to shingles that had a bright white coat of paint.?.
My guess is, the painted roof would not be re-radiating heat inside (under the roof)
at
anywhere near the rate of the dark roof.
One web hit on the topic..
Energy Efficiency Delivered by “Cool Roof” Reflectivity - Cool Zone - Duro-Last Roofing, Inc.